//
//
//import com.bit.demo1.date;
//
// class DA {
//    public static void main(String[] args) {
//        date d1 = new date();
//    }
//}
class DA{
    public DA(String s){
        System.out.print("B");
    }
}

 class Derived extends DA{
    public Derived (String s) {
        super(s);
        System.out.print("D");
    }
    public static void main(String[] args){
        new Derived("C");
    }
}